Synthesis of new organometalloids, particularly organometalloids functionalized with an unsymmetrical 1,1-disubstituted alkene is one of the most important aspects in organic synthesis chemistry, since organometalloids have been found in broad applications due to their unique properties such as electrical conductivity, magnetism, and chemical reactivity.
Methods for preparing organometalloids functionalized with an unsymmetrical 1,1-disubstituted alkene in the art may generally rely on expensive starting materials. Most of the methods are stoichiometric in nature or suffer from significant waste disposal problems in a large scale (e.g. phosphine oxide, arylsulfonate, titanium/aluminum salt, silyl ether and halides) or substrate availability.
There are only very limited availability and choices of 1,1-disubstituted alkenes and homoallylmetalloids on the market, mainly constrained by the availability of natural products, petroleum cracking and selective dehydrogenation of several alkanes. According to the Sigma-Aldrich product catalogue, there are only around twenty 1,1-disubstituted alkenes available in stock (a very low amount compared to aromatic alkenes and alpha-alkenes, http://www.sigmaaldrich.com/chemistry/chemistry-products.html?TablePage-16274429).
Synthesis of organometalloids functionalized with an unsymmetrical 1,1-disubstituted alkene from vinylmetalloids and α-olefins may suffer from side reactions such as olefin isomerization/oligomerization, self-dimerization, hydrogenative dimerization, dehydrogenative silylation, silylative coupling, and Hiyama coupling, resulting in a mixture of regioisomers and a significant amount of toxic transition metal waste.